Airbag deployment sensor tape folding loom

ABSTRACT

A tape for use within an airbag deployment sensor is formed in an apparatus that has a housing that receives an elongated tape within a tape slot. A pin base with upwardly protruding parallel pins is positioned forward of the tape slot and reciprocates vertically. A tray is mounted to the housing forward of the pins which has an upwardly facing shelf which receives the elongated tape thereon as it is folded. Parallel blades are mounted to the housing and are slidable in the front to back direction. Each blade is movable from behind the pins to extend between two pins such that portions of the blade protrude forward of the pins. Each blade may thus extend across the tray shelf to engage with the tape extending through the tape slot to impose a fold on the tape.

FIELD OF THE INVENTION

[0001] The present invention relates to airbag deployment sensors ingeneral, and more particularly to the apparatus for fabricating the fanfolded tape used in sensors to determine the progress of airbagdeployment.

BACKGROUND OF THE INVENTION

[0002] Airbags are typically used as part of a vehicle safety systemthat includes seat belts and other safety systems. A crash eventtriggers an airbag deployment algorithm that determines whetherinitiation of the airbag will be conducive to a positive outcome for theseat occupant. These automated decisions are made in a very short periodof time, and may at times be subject to revision in light of theadditional data that is provided over the course of the crash and themilliseconds immediately following impact. It is particularly importantto determine if the airbag is impacting a vehicle occupant before theairbag is fully or nearly fully deployed. If the seat occupant comesinto engagement with the airbag too soon, it is preferable to instantlydeflate the bag rather than continue to expand it. Thus sensors arerequired to determine when the occupant engages the airbag, or, moreparticularly, when the deployment of the airbag is restricted by theencounter with a seat occupant.

[0003] One known type of sensor that is taught in EP 0990567A1 employs aplurality of tapes which extend between the front of the airbag and atape dispensing cartridge mounted on the airbag housing. Tape extractionsensors within the cartridge monitor the rate at which tape is withdrawnfrom the cartridge and thus can detect airbag impact with an occupant bya decrease in airbag velocity. One compact mechanism for storing thetape within the cartridge before deployment is to fold the tape into aseries of fan folds. Such a tape storage approach is very volumeeffective, and does not require rotating parts. With a so-called fanfold the tape does not buildup momentum the way a spool of tape can.

[0004] What is needed is an apparatus for rapidly and repeatedly formingthe required pleats in the airbag deployment sensor tapes.

SUMMARY OF THE INVENTION

[0005] The airbag deployment sensor tape folding loom of this inventionis used for fabricating an airbag deployment sensor tape. The loomcomprises an apparatus that has a housing that receives an elongated andunfolded tape within a tape slot, the tape extending from a housinginlet to a housing outlet. A pin base is mounted to the housing forreciprocating vertical motion, and is positioned forward of the tapeslot. Parallel pins extend upwardly from the pin base. A tray is mountedto the housing forward of the pins which has an upwardly facing shelfwhich receives the elongated tape thereon as it is folded. Parallelsliding blades are mounted to the housing and are slidable in a front toback direction. Each blade is movable between a first position rearwardof the pins to a second position extending between two pins such thatportions of the blade protrude forward of the pins. Each blade in thesecond position extends across the tray shelf, and the blades are thusengageable with the tape extending through the tape slot to impose aplurality of folds on the tape.

[0006] It is a feature of the present invention to provide an apparatusfor uniformly producing tapes having a series of fan folds therein.

[0007] It is another feature of the present invention to provide anapparatus for automating the production of folded airbag sensor tapes.

[0008] It is an additional feature of the present invention to provide adevice for speedily forming an airbag sensor tape with a sequence ofrepeated folds for storage in a compact volume.

[0009] Further features and advantages of the invention will be apparentfrom the following detailed description when taken in conjunction withthe accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010]FIG. 1 is an exploded isometric view, partially broken away insection, of the airbag sensor tape loom of this invention, shown with apartially folded tape.

[0011]FIG. 2 is a top plan view of the tape loom of FIG. 1, with thecover partially broken away in section, to show the tape in the processof being folded.

DETAILED DESCRIPTION OF THE INVENTION

[0012] Referring more particularly to FIGS. 1-2, wherein like numbersrefer to similar parts, the tape folding apparatus 20 is shown. Theapparatus 20 has a housing 22 that may be formed of plastic, metal orother material. The housing 22 is generally box-like and has a base wall24 with an upwardly extending front wall 26, a left sidewall 28, and aright sidewall 30. A notch is formed along the upper edge of the leftsidewall 28 that defines a tape inlet 32. A similar notch is formedalong the upper edge of the right sidewall 30 that defines a tape outlet34. A tape slot 36 extends between the inlet 32 and the outlet 34.

[0013] A sliding tray 38 is located within the housing 22 forward of thetape slot 36. The sliding tray 38 has an upwardly facing horizontal tapesupport surface 40 onto which an elongated tape 42 extends during thefolding operation. A tape compartment 31 is defined within the walls 26,28, 30, forward of the tape slot 36 and above the sliding tray 38. Thetray 38 extends between a tray slot 44 in the left sidewall 28 and atray slot, not shown, in the right sidewall 30. An upper flange 46extends upwardly from the surface 40 of the tray 38. The upper flange 46is substantially parallel to the left sidewall 28, and is positionedadjacent the inside of the right sidewall 30 at the beginning of theprocessing of a tape 42, and serves to compress a folded tape when thetray 38 is slid toward the left sidewall 28, as described more fullybelow. The sliding tray 38 is thus slightly more than twice as wide asthe housing 22 and has an outside segment 48 which protrudes to theright of the flange 46 and extends exterior to the housing at thebeginning of the folding process.

[0014] For purposes of storage within a sensor device, the tape 42should be compactly formed with a series of fan folds 50. As shown inFIG. 1, the tape 42 may be preprinted or otherwise treated to have aseries of alternating dark and light stripes 52. The fan folds 50 areimposed on the tape 42 by the interaction between a series of slidingblades 54 and vertically extending pins 56.

[0015] The pins 56, which may be formed of metal or other rigidmaterial, extend upwardly from a pin base 60 which extends from side toside rearward of and beneath the sliding tray 38. The pin base 60 isarranged for reciprocating vertical movement within the housing 22.Various mechanisms may be employed, for example, as shown, horizontalrods 62 may extend outwardly from the ends of the pin base 60 to ridewithin vertical slots 64 formed in the housing sidewalls 28, 30. Thepins 56 are parallel to one another and equally spaced apart. The pins56 extend above the level of the sliding tray 38 support surface 40,preferably too at least the height of the tape 42 which is beingprocessed.

[0016] The blades 54 run from front to back within the housing, andextend within parallel blade slots 68 formed in the housing 22 rearwardof the pins 56. The blade slots 68 have floors, not shown, which supporteach blade 54 at a level to allow it to slide freely across the traysupport surface 40. The blades 54 are retained within the blade slots 68and are prevented from tipping by a restraint plate 70 which is fastenedto the housing 22 to overlie the blade slots 68 and the blades 54retained therein.

[0017] Each blade 54 extends perpendicular to the tape slot 36 and iscentered to project out over the sliding tray support surface 40 at aposition between two pins 56. As shown in FIG. 2, each blade 54 may beindependently operated to cross the tape slot 68, engage a tape 42, andextend the tape in a fan fold across the sliding tray 38. The blades 54are operated one after the other, starting from the inlet end of thehousing, to add additional fan folds to the tape 42 until the slidingtray 38 is filled with folded sections of tape. As the blades 54 areoperated they draw additional tape 42 from the direction of the onfolded portion of the tape into the apparatus 20. The housing 22 has atransparent cover 72 which is hinged to the front wall 26 and which isclosed over the sliding tray 38 during operation. The cover 72terminates at a short distance from the restraint plate 70 so that thetape slot 36 is not obstructed by the cover.

[0018] To remove a folded tape 42 from the apparatus 20, the blades 54are withdrawn between the pins 56. To facilitate the uniform withdrawalof the blades 54, each blade is preferably provided with an outer notch74. The notches 74 of all the depressed blades 54 may be simultaneouslyengaged by a retraction member 76, shown in FIG. 1. The retractionmember 76 has downwardly opening slots 78 to correspond with each notch74.

[0019] After the blades 54 are withdrawn, the rods 62 are depressed tolower the pin base 60 and the pins 56 below the level of the slidingtray support surface 40. The pin base 60 may be held by friction or theoperator in either a depressed condition or in a raised position. Theoutside segment 48 of the sliding tray 38 is then pressed to urge theflange 46 against the folds of the tape and to compress the fan folds 50into a compact arrangement. The folds will be restrained between theleft sidewall 28 and the flange 46.

[0020] Once the folds have been compressed, a user may, flip open thecover 72 about its hinges 80, grasp the completed folded tape and removeit from the apparatus 20. To facilitate engagement of the folded tape bythe user's fingers, a finger relief opening 81 is defined in the leftsidewall 28 forward of the tape inlet 32, and a similar finger reliefopening 82 is formed along the upper edge of the sliding tray flange 46.

[0021] It should be noted that, although the apparatus 20 has been shownas a manually operated fixture, it may readily be automated utilizingclosing cams and stepper type motors to operate the blades, theretraction of the pins, and the insertion of the raw tape.

[0022] The operation of the apparatus 20 is as follows. First, with thesliding tray 38 fully extended to the right, the cover 72 is opened.Next, the pins are returned to the up position. A fresh, unfolded, tape42, approximately 91.5 centimeters (36 inches) long, is then threadedthrough the tape slot 36, leaving approximately 2.5 centimeters (1 inch)of tape extending outwardly of the inlet 32. The remainder of the tape42 will extend through the tape slot and protrude through the outlet 34.The cover is then closed, and the 2.5 centimeters (1 inch) of tapeextending from the tape inlet 32 is held against the left sidewall 28.The blade 54 closest to the left sidewall 28 is slid into the housing,and then the remainder of the blades are advanced, while holding theearlier depressed blades in their depressed position. Once all the fanfolds have been imposed on the tape, the retraction member 76 is used tomove the blades to the open position. Once opened, the blades may bemoved slightly forward to reposition the tape folds against the pins.The blades may then be retracted again. The pins are then moved to thefull down position. The tray is slid to the left, thereby closing andcompressing the tape folds. The cover is then opened, and the foldedtape removed. If necessary, the tray may be moved slightly to the rightto facilitate removal.

[0023] It is understood that the invention is not limited to theparticular construction and arrangement of parts herein illustrated anddescribed, but embraces all such modified forms thereof as come withinthe scope of the following claims.

I claim:
 1. An apparatus for folding elongated tapes, the apparatuscomprising: a housing having portions defining a tape slot, and portionswhich define an inlet to the tape slot and an outlet from the tape slot;a pin base mounted to the housing for reciprocating vertical motion, andpositioned forward of the tape slot; a plurality of parallel pins whichare fixed to the pin base and which extend upwardly therefrom; a traymounted to the housing forward of the pins, the tray having an upwardlyfacing shelf which receives an elongated tape thereon; and a pluralityof parallel sliding blades which are mounted to the housing and areslidable in the front to back direction, wherein each blade is movablefrom a first position rearward of the pins, and a second positionextending between two pins such that portions of said blade protrudeforward of the pins, wherein each blade in the second position extendsacross the tray shelf, the blades being thus engageable with a tapeextending through the tape slot to impose a plurality of folds on thetape.
 2. The apparatus of claim 1 wherein the housing has a first wallwhich extends upwardly above the level of the tray shelf, and wherein aflange extends upwardly from the tray within the housing, the flangebeing substantially parallel to the housing first wall, such that thetray may be advanced to compress the folded tape between the flange andthe first wall.
 3. The apparatus of claim 2 wherein the flange hasportions defining an upwardly opening finger relief opening, and thefirst wall has portions defining an upwardly opening finger reliefopening.
 4. The apparatus of claim 1 further comprising a cover that ishinged to the housing and which in a first position extends over andcovers the tray, and in a second position allows access to the tray. 5.The apparatus of claim 1 wherein the housing has a first sidewall and aparallel second sidewall, and wherein parallel tray slots are defined inthe first sidewall and the second sidewall to receive the tray extendingtherethrough, and wherein portions of the tray extend outwardly from thesecond sidewall prior to the imposition of the plurality of folds on thetape.
 6. An apparatus for folding elongated tapes, the apparatuscomprising: a tape supporting tray; a housing having portions definingan interior tape compartment, into which the tray extends; portions ofthe housing defining a tape slot communicating with the tape compartmentand having an inlet and an outlet; a plurality of pins which projectupwardly into the tape compartment, the pins being movable to bepositioned below the tray, the pins being positioned forward of the tapeslot and rearwardly of the tray; portions of the housing which define aplurality of parallel blade slots communicating with the tapecompartment; and a plurality of blades, each blade being mounted in oneof said blade slots, wherein each blade is movable from a first positionrearward of the pins, and a second position extending between two pinssuch that portions of said blade protrude forward of the pins, whereineach blade in the second position extends across the tray shelf, theblades being thus engageable with a tape extending through the tape slotto impose a plurality of folds on the tape.
 7. The apparatus of claim 6wherein the housing has a first wall which extends upwardly above thelevel of the tray shelf, and wherein a flange extends upwardly from thetray within the housing, the flange being substantially parallel to thehousing first wall, such that the tray may be advanced to compress thefolded tape between the flange and the first wall.
 8. The apparatus ofclaim 7 wherein the flange has portions defining an upwardly openingfinger relief opening, and the first wall has portions defining anupwardly opening finger relief opening.
 9. The apparatus of claim 6further comprising a cover which is hinged to the housing and which in afirst position extends over and covers the tape compartment, and in asecond position allows access to the tape compartment.
 10. The apparatusof claim 6 wherein the housing has a first sidewall and a parallelsecond sidewall, and wherein parallel tray slots are defined in thefirst sidewall and the second sidewall to receive the tray extendingtherethrough, and wherein portions of the tray extend outwardly from thesecond sidewall prior to the imposition of the plurality of folds on thetape.
 11. A method for folding an elongated tape for use within anairbag position sensor, the method comprising the steps of: inserting anelongated tape into a tape slot within a housing having portionsdefining the tape slot, and portions which define an inlet to the tapeslot and an outlet from the tape slot, such that a length of tapeprojects from the housing tape slot outlet, the tape extendingrearwardly of a plurality of parallel vertically extending pins mountedto a pin base; sliding a first blade forward between two of theplurality of pins, such that the blade engages against the tape withinthe tape slot, and crosses over a tray mounted within the housingforward of the pins, to thereby impose a fold on the tape; after slidingthe first blade, sliding a plurality of latter blades one after theother to extend across the tray and impose a plurality of folds on thetape; depressing the plurality of pins below the folded tape; retractingthe blades; and compressing the folded tape on the shelf and extractingit from the housing.
 12. The method of claim 11 wherein each blade has arearward notch, and wherein the step of retracting the blades comprises:engaging a retraction member with a plurality of slots with the rearwardnotches of the blades; and moving the retraction member rearwardly tosimultaneously retract the engaged blades.